2013 Mercedes-Benz SL63 AMG

The latest SL AMG adopts Merc's twin-turbo 5.5-liter V-8.

Attention, landed gentry and Hollywood elite: The previous-gen SL63 sitting in your pea-gravel driveway is outdated and should be disposed of immediately. Mercedes-Benz and AMG have now birthed its successor, a new SL63 created by marrying the SL-class chassis with AMG’s fire-breathing, twin-turbo 5.5-liter V-8.

Like many current AMG models, the new SL63 hardtop convertible can be had in two strengths, but even the "base" version leaves little to be desired: It makes 530 hp at 5500 rpm and produces a maximum of 590 lb-ft from 2000 to 4500 rpm. There is an optional Performance package, which raises power to 557 hp and maximum torque to 664 lb-ft (available from 2250 to 3750 rpm). The engine is internally coded M157 and is an all-aluminum piece with direct injection and variable valve timing. As with the previous SL63, output is transmitted to the rear wheels through a seven-speed automatic transmission that uses planetary gearsets per usual autobox practice, but skips a torque converter in favor of a wet clutch pack.

Acceleration should be strong: 60 mph is claimed to arrive in just 4.2 seconds, and top speed is governed at 155 mph. The numbers change to 4.1 seconds and 186 mph with the Performance pack. Helping performance—and likely agility—is the fact that this SL63 is said to weigh some 275 pounds less than its predecessor. The weight loss was achieved through widespread use of lightweight materials throughout the car, including aluminum, magnesium, and carbon fiber, with a little high-strength steel thrown in, too. The front steering knuckles and suspension arms, as well as virtually the entire rear multilink suspension, are made from aluminum. If Mercedes’ weight-loss number holds up, we figure the new car will come in at 4200 pounds or so.

The standard 19-inch rollers wear 255/35 rubber up front and 285/30s at the back; staggered-diameter wheels are an option, with 19-inchers up front and 20s fitted to the rear. Other options beyond the aforementioned Performance pack (which also brings a new steering wheel, a limited-slip diff, and red-painted brake calipers) include keyless start, a bundle of nanny tech (lane-keep assist, blind-spot monitoring, brake assist, and radar cruise control), an uprated Bang & Olufsen audio system, heated and ventilated seats, and Mercedes’ trick Airscarf neck warmers.

The AMG treatment does wonders for the slightly awkward styling of the new SL. The air intakes are more angular, while the grille is more pointed—and actually aligns with the headlights. The rear end gets more aggressive through the fitment of four rectangular exhaust tips and a lip spoiler. The interior is only slightly modified, with an AMG-specific gear selector and an IWC-badged analog clock among the notable changes. The steering wheel trades the flamboyant "Mercedes-Benz" script in favor of a more sober "AMG" logo.

This most powerful and most expensive—figure on a price of at least $140,000—SL will make its public debut at the 2012 Geneva auto show and goes on sale in the U.S. later this year.